1. Technical Field
The present disclosure relates to the field of processing audio signals. In particular, to a system and method for dynamically mixing audio signals.
2. Related Art
When mixing two or more independent audio signals together, for example, multiple parties on a conference bridge or separate microphones, there is a known issue related to dynamic range and noise. The more audio signals that are added, or mixed, together the more the noise grows while the desired audio content remains at the same level. The mixed output signal may have a reduced signal to noise ratio when compared to any one of the independent audio signals. The overall noise level may be kept lower by averaging the audio signals, but the averaging process reduces the overall gain of each audio signal.
A voice activity detector (VAD) may be applied prior to mixing where all non-voice content bearing signals may be suppressed so that the noise does not add, but this type of suppression results in an unnatural gating sound and may not be suitable for audio signals that are not voice content bearing, such as music. Each audio signal may be subject to a noise-normalization scheme, but again noise-normalization introduces gating for some sources that may be perceived as unnatural.